1. Ph.D. Student, School of Civil and Resource Engineering, The Univ. of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia (corresponding author).
2. Federation Fellow, Centre for Offshore Foundation Systems, The Univ. of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia.
3. Professor, Geosystems Engineering Group, School of Civil and Environmental Engineering, Georgia Institute of Technology, 790 Atlantic Dr. N.W., Atlanta, GA 30332-0355.
4. Principal Geotechnical Engineer, Sinclair Knight Merz (SKM), P.O. Box 2500, Malvern, Victoria 3144, Australia. E-mail: nramsey@skm.com.au